Apparatus for heating water.



J.E OAP& APPARATUS FOR HEATING WATER.

APPLICATION FILED DEO. 13,1910.

1,018,408. Patented Feb. 27,1912.

2 BHEETS-SHEBT 1.

J. E. CAPS.

APPARATUS FOR HEATING WATER.

APPLICATION FILED DEU.13,1910.

. 1,018,408. Patented Feb.27, 1912. v

v 2 SHEETS-SHEET 2.

PATENT OFFICE.

JOHN E. cars, or w inma'r'ra, rumors.

arraim'rvs. FOR HEATING WATER.

To' all whom it may concern: 7

Be it. kn'mvn that I, Joni: 'E. CAPS, citi zenof the United 'States; residing at Vil- -mette, in the county of Cook and State of Illinois, have invented certain new and useful. Improvements 'in "Water-Heating Apparatus; and Ido hereby declarethe following to be a full, clear, and'exactdescription of the invention, such as will enable others 10. skilled in the art to which it appertains to.

make and use the same. This invention relates to improvements in water-heatiug apparatus and has for its object to provide means for 'automatically controlling the temperature of the waters The invention consists in the features of construction and combinations of parts hereinafter .fully described and claimed.

In the accompanying drawings illustrating this invention: Figure -1 is a viewpartly in elevation and partly'in .section shtuving water heating apparatus constructed' in accordance \vith my invention. Fig. '2 is a detail sectional view showing one of the valves employed. Fig. is a detail view .in elevation showing the means actuating the valvefshown' in Fig. 2--. Fig. 1'- is a fragmentary detail sectional view of one end of a thermostatically actua'ted lever showing-the connection S thereof with the stem of a valve. F ig.'5 i's'a fragmentary detail view 'showin tion between va valve stem and?) actuating the valve. The invention relates particularly" to water heating apparatus in which thelmain heating medium employed; is waste eirhau steam. "-1."

The present invention .relat ticularl .to 'ii'provem'ents 'ipon -tl ratus s Iowa and d and-in addition: ieret a actuating-valves .coi t-roll iiig the int r fr a. m n't' fs i 7 5617. e ,returnfto the lat-tersof watererefrom-. The said float serves to lite 8;, constantlw-ater level in'the rese'r I Specification of Letters Patent. Patented Feb. '27, 1912. Application filed December 18, 1910. Serial No. 597,161.

a given maximum temperature. Third to. provide means wherehysurplus heat units" lure absorbed by a secondary water supply to avoid waste.

The several objects of the inventiortare attained -by -mea-ns of the apparatus shown and which I will now proceed to describe. Thefappa'ratus' comprises the reservoir 1 'which is fed from a street main or other source of supply admitted through the-pipe controlled by the float-controlled valve 2. soften-the same and constitutes the cold ,wate'r supplyto service pipe points of consumption such as washing machines, dye or bleaching vats, etc. Ad jacent'said reservoir 1 is a hotwater reservoir'3 the. latter being of less height than said reservoir. I-fcr reasons which will here, inafter appear; The hot water reservoir 3 receives its supply of water from the reservoir lpand delivers it through the "service pipe?! to points of consumption such as above mentloned. Adjacent the tank 3-is an This water is preferably treated 'to 2 leading-to exhaust "steam hood 5 fed from the exhaust pipe: 6- 0 f a steam power plant,- the steam passing into the-said hood being condensed 1113'- z'iliif'e ct contact with water f ed to said 7 gm.

I 'I-heila ter is conn end; O fithe'Pump 'T offthe thermostat,

"ushereinafter described, with the float 17 in theflireservoir -3,. By means' of these loonnectiom'fhe water contained in the reser-' I v'oir- 3' ls-repeatedly: passed through the hood 5'jas will be obvious. l 4

ieserv'oir 1 is alsoconneeted-with the ivith pipe .the pump;7- thrfp'hgla" the pipe 8 3S hing the heat units of the: throu h thepipe' suction end of the pump 7 by means of pipe ,18 connecting with pipe 19, constitnting a member of the thermostat, which 1n turn connects withpipe 20 and-pipe 13. In' the between the ends of said short arm with the 5 pipe are, interposed a manually operated one arm of a-hell crank lever 39,, the latter valve 21, a check valve '22 and a yalve or being suitably p votally supported at its cock 23, the stem of the latter be ng conelbow and connected at the free end of its nected with the lever 24 between the'ends other arm with the free end portion of said thereof, said lever carr ing a .weight 25 fat lever by means of a link d0. On the other 10 one end and being suita ly connected atsaid end ofthe lever 37 is a weight 43 which as end with the float 17 bymeans of the cable said valve is opened and closed respec- 26. Said lever 24 is connected at. its other tively passes to opposite sides of the vertical end by means of the link 27-with the lever 28 plane of the axis of.oscillation of said valve on the-stem of the valve 16, said valves 16 and said lever. The connection between =15 and 23 being thus simultaneously actuated said lever 37 and said link 38 is made by in accordance with variations in water lever in the reservoir 3. The valve 23 is closed by attainment of the high water level in the reservoir 3 and is opened as the said level is lowered, the valve 16) being closed as the valve 23 is opened, the degree of opening and closure of the respective valves depending upon the degree of variation in the water level in said reservoir 3. The said pipes 11 and '19 are coupled by means of a member 29 relatively to whichthe other end portions of said pipes movefduring expansion and contraction thereof. An L-sha ed lever 30 ispivotally .connected at the co end of its short arm with the pipe 11 and pipe 19, the long arm of said le'ver being adapted to be swung through a relatively long are by a relatively limited movementof.

the pivotal connections of the short arm 'relatively to each other due to expansion and contraction of said pipe-11. Thmfree end of-said' lever 30 is connected with the stem of a valve 31 interposed in a pipe 32' water when said valve is closed. On the stem of said valve 35 there is mounted a lever 37 which is connected at one'end by means of the .lin-k38 with the free end of roviding a longitudinal slot in the latter in which a crank-pin on the first-named end ,3?- passes thevertical plane of its-axis of rotation in either direct-ion it will be 'free to fall'and thus impart sudden opening or closing movement to said valve, either through the entire arc of movement of said direction. --By rendering the lever 37 rigid with the stem of the valve 35, asshown in Fig. 4+, the'primary opening or closing movement of the valve will be in accordance with the rapidity of-movement of the lever 30 or relatively gradual, while thefinal openingor closing movement, thereof would .be sudden. ,-I-f, however, as shown in--Fig. -5- the lever-.37 is rotatablymounted on the valve stem and isequipped with a pin or projection 44 engaging eithen end wall the segmental recess 15 in a collar 46 rigidly mounted on the val ve-stem, the valve will be moved solely in either direction by the dropping of the weight 13 and thus its of said lever 37 engages so that as said lever 4 valve or during its final movement in either 1 connected at one end with a source of sup: ntire movementin either direction renply of live steam andat its other-end deie S dd nlivering into the reservoir 3, the said valve By means et S e s Wand 48 proiectbeing adapted to'be opened when the pipe 11 ing into the ends of the slot in the end of contracts due to the passage. therethrough the 'link- 38, the latter is practically short- 45 of Water of a lower temperature than that ened or lengthened at will thus enabling the i t d d t be m i t ined in s id seropening and closure of said valve 35 with 1 i;- 3 relation to movements of the lever 30 to be p Th i s i connected b t e it d regulated'at will, this-being important in by means of a T'coupling 33 with a pipe controlling the maximum temperature of b0 34 d li i i t th reservoir 1 dja t the water in the reservoir 3 as will hereinthe upper end thereof, the delivery end of a ter appear. said pipe 34 being preferably disposed at -The connection of the lever 30 'with the a hi h l ti th th di h g d fstem 49 of the valve 31 is shown in detail said pipe 8 so as to resist delivery into said n g- -4-.-, sa d stem p ss g hr u a 55 reservoir 1 by gravity. This constitutes the sleeve 50 having threaded engagement. with simplest means for resisting such delivery a threaded opening in said lGi 1,.Snid sleeve although mechanical means for accomplishbeing-turned'by means'of the head 51 thereing the same purpose may obviously be subof and being locked, against rotation by stituted if desired. In the latter there is means of the head" 51 thereof and being so also interposed above said'T coupling a locked against rotation hv means of a lock valve 35 of the so-called fly type. This nut 52; The opening in the sleeve 50 is 'anvalve s shown in detail in Figs. and nu'larly' "enlarged at one end to receive one -3, In which it willbeseen' that the valve end portion of-a compression spring bearproper therem is provided withan'opening ing-at its projecting end upon-a collar 54 on 5 36 for the passage of a limited quantity of said valve-stem 49. v A similar compression 13C j stnnption and'i'thgat it is desired [to maintain spring 55 is interposed between the other end of the sleeve 50 and a collar 56 on said valve-stem 49. I'hu's the movements of the lever 30 in either direction are transmitted to the valve-stem through said springs 53 and 55, the lever being ca able of continuing its movement in either direction beyond the limits of movement of said valve-stem.

On the lever 30 is a projection 57-0n one edge portion of which 1s a graduated scale 58 relatively to' which the sleeve 50 is adjusted to determine the normal minimum temperature to be maintained in the reservoir 3, said graduatio-ns being suitably numbered to indicate different temperatures. It thetemperature of the water passing through the pipe 11 is less than the temperature indicated oppos te the upper face 1 of the head 51 of sa1d sleeve 50 a movement of the lever in adirection to open the valve .31 will occur; I The operation of my said apparatus is as follows Assuming that the reservoir 3 has; just been tilled with co d water and that the reservoir 1'is-also 111 of thesame. Exhaust steam is passed up through the pipe. 6 into thehood '5 and the pump/(is delivering water into the latter. As the water level Qinf the reservoir 3 is at the normal point the valve 16.will be open and the valve 23 closed.' The cold water entering the suction end of the-pump 7. passes through the pipe .11 from said reservoir 3 and said ipe is therefore contracted so that the va ve 31 is open and admitting live' steam to sa'idreservoir 3 to heat the water therein. At the same time the 'water'delivered from' the pump 7 into the-hood {iiis *brought into intimate contact with the exhaust steam thereby condensing the latter I andabsorbing its heat units. The water -is maintained in constant circulation from the reservoir 3 throughthe pipes 1-1, 12 and 13 and through the pump. 7 and pipe 8 and ex} haust ho'od- 5 back"to the reservoir. The water is thus relatively rapidly heated, the rapidity of-attainment of a;h1gh Stem era-. ture-being, of-course, dependentto a arge f extent -.upon the volume "of exhaust steam pass'in .in'tothe hood and also upon the ex tent 'o consumption oi; -fwater from said reservoirQWhile -the-latter is being heated; Assuming, ,however, that there is no con-1 the temperature of water: in s'aidreservoir t slee so ti iii reservoir '1 takes place.

mittin or less cbnstantly withdrawn at the-various to pass through-the hood 5 and into Contact with the exhaust steam of higher 'temperature itwill bectme gradually hotter. It 's desired, however, to prevent the waste of exhaust steam to "prevent the attainment by agent. We will assume that the maximum temperature desired to be attained is 200' degrees f Fa'hr. This is controlled by the valve 35 and the set-screw 47, it being necessary tha't'said valve be closed as soon as water passing the temperature of the through the pipe 11 attains said temperature; The farther said set-screw 47 projects into -s'aidjslot the less the upward movement of the free end of said lever 30 necessary to throw the lever 37 into position to cause a ldsure of said valve 35. flfn the same way .the water of a temperature so high ,asto render it ineffectual as a steam condensing the 'set screw .48 c ont-ro1s the time of reopening of the'valye'35, as will be. obvious;

As soon 'as theamlve 35 is closedonly a small portion of the W'ate-r delit'ered from the pump 7 will be enablecbto pass into the hood 5, the remainder thereof being deflected throughthe pipe 3'4 into the reservoir 1, the resistance of thevalve 35 to. the pas sage of water servingto overcome the difference in elevation between the delivery end of the-pipe 8 and the delivery end of the pipe Stto 'deliverlthrough the latter. As the discharge. into the reservoir 3 decreases by reason of the closure of the valve 35 and i the suction from said reservoir 3 remains the same, the water level in said reservoir 3 will obviously become lowered thus partially or entirely closing'the valve 16 and to a similar extent opening the valve 23, whereby thesuotion from the reservoir 3 is decreased or entirely shut off and suction .from the delivered into the reserv'oir- 3 after passing- -T e water 'frorn through the hood and; ot course, absorbing heat' units from the }exhauststeam, the major-portion of said water being-obviously returned to *t-he' reservoir 1.v The injection I of cold waterintothe'reservoir 3- thus effecthe position or th f ed-'-wi ll obvious] "decrease the said maxmru'znwtem 1 3 its free end thereby. openingsaid valve 35 stconsulerabl'y fbe sw v n -3 f gme Fahr. the-lever 30 will move downw'ar e said, temperature through theengagement-ofthe set-screw 48 t the crank pin offthe' lever-37 and ad-.'

e quantityof colder water; the "normal .m'

vlar

great er.

thermostat performs the double function of regulating the minim um as well as the 1naximum temperature of the Water contained in.the reservoir 3. The reservoir 1 acts prima rily as a source of supply of softened water to the reservoir 3 and fas an absorber of surplus heat units incapable of absorption by the water in the reservoir 3 without in during waste of exhaust steam.

The apparatus is designed to utilize exhaust steam as a. heating medium exclusivcly, the live steam supply being used only in the event, of excessive consumption of hot water.

Bypassing the water from, the reservoir 3 eontimiously through the hood 5 and back tothe reservoir, stratification in the latter is prevented and a temperature varying between the'fixed minimum andmaximun. is very accurately maintained, the capacity-0t the reservoir 3 being regulated by the needs of the plant, it being found that where the capacity need is greater, the power plant is proportionatcly larger and'the waste of exhaust steam is likewise proportionately I desire to direct particular attention to thei'act that an ii'iterchange of waters from the hot to the cold water reservoir and vice versa takes place only after the attainment tit-the predetermined maximum temperature in the reservoir 3 and that such interchange is 'e'i'itirely controlled by the valve 35. Such interchange 'ta'lves place only temporarily, 'until the water levcl'in the reservoir fallen sulliciently to cause coi'i'u'ilctc closureot' the valve Latter which water is delivered only from reservoir 1 to reservoir part of said water being returned to the reservoir '1' until the valve 35 is again "opened. i

:l'cla im as my invention:-

'l In a ipa-ratus of the kind specified, the

combination with a hot Water reservoirya constantly active heater, a pump for pass ing-ivatcr from said reservoir continuously into heatabsorbing'relation to said heater water therefrom into said hot water reserthe connections between said respective reservoirs and said suction end of said pump, a float in. said hot water reservoir actuating -both said valves and adapted to open one thereof as the other closes, a pipe leading from the discharge pipe from said pump to said cold water reservoir, and means for normally resisting the delivery of Water thcrethrough, of thermostatically controlled means interposed in said delivery pipe from said pump for deflecting 'tlow therefrom into said cold Water reservoir againstthe resistance oi said flow.

2. In apparatus of the kind specified, a hot water and a cold water reservoir, a con stantly active heater comnnmicating at its delivery end with said hot water reservoir, :1 pump connected at its delivery-end with said heater, a pipe establishing communication between said delivery end of said pump and said cold water reservoir, means for normally ,rosisting flow through said pipe, normally open connection between. the suction end of said pump and said hot Water reservoir, norn'ially' closed connection be tween the. suction end of said pump and said cold water reservoir, a float in said hot Wat-- ter reservoir controlling both said connections and adapted to open the latter as the former is closed, and a. thermostatically controlled valve in the delivery pipe from said pump adapted when closed to cause a flow into said cold water reservoir against the resistance ofi'ered thereto, there. being a by pass opening in said valve through which a part of the Water is delivered by the pump ipto said heater.

In apparatus of the kind specified, a.

hot Water and a cold 'Water',rcservoin a constantly acti e heater communicating at its-delivery (.11Fl.\Vit-l'l said hot- Wat-er reservoir, apump connected at its delivery end with said heater, a pipe est a-blishin g communication between said delivery end'of said pump and said cold'water reservoinvmcans for normally resistingflow through said reservoir, normally closed connection between the suction end of said pump and said cold water reservoir, a float in said hot Water.

a ga -inst the resistance thereto, and FtillGlll'JO- I D statically operated lever operatively conand back to said reservoir, a reservoir for" cold water, connectionbet vejn the same and ,the"'suct1 on end of said-pump for passing delivery end with said hot water reservoir,

pipe, normally open connection between .the I suction end of said pump and said hot water .water heater, a cold water reservoir norhas a ump connected at its delivery end with sald heater,'a pi e establishing communica tion between sai delivery end of said pu'rnp and said cold water reservoir, means for 4 5 normally resisting flow through said pipe,

open connection between the suco ai normall tion en s d pum and said hot water reservoir, normally .0 osed connection between the suction end of said pump and said cold water reservoir, a float in said hot water reservoir controlling both said C011? nections and adapted to open the latter as the former is closed, a normally inactive, heater disposed in said' hot water reservoir, a valve controlling the same, a valve in the delivery pipe from said pump adapted when closed to cause a flow into said cold water tank against the resistance thereto, there being a by-pass opening in said valve through which a part of the water is delivered bythe' pump into said heater, and a thermostatically operated lever operatively GQnnected with both said valves.

5. In apparatus of the kind specified, a hotwater reservoir, a normally ipactive mally closiethmeans establishing feed con nection from the same to said hot water reservoir, normally inactive means for deliver-- ing hot water into said cold water reservoir, a valve controlling said last-named means, a valve controllin the activity of said heater, a thermostatically actuated lever operatively connected with said last-named valve and adapted to open the sanie'when the water in said hot water reservoir falls below a given temperature, and operative connection between said lever and said firstnamed valve for actuating the latter to cause a, flow of hot water into said cold water res- "ervoir when the temperature of the water in said hot water reservoir rises above a given temperature, and means actuated by variations in water level in said hot water reservoir for causing a flow of water from said cold Water reservoir thereto;

6. In apparatus of the kind specified, a source of heat, a hot water reservoir, means for continuously passing water from said reservoir to said source of heat and back to said reservoir, a cold water reservoir, means establishing a feed connection from the cold ,water to the .hot water reseri'oir, means establishing connection from the hot water .to the cold water reservoir, a thermostatically actuated diversion valve, controlling the last-named connection; and means actuated by variations in water level in said hot water reservoir controlling the first-named connection.

7.1 :1 apparatus of the kind specified, a

'source of heat, a hot water reservoir, means for continuouslyp'assipg water from said reservoir to said source of heat and back to said reservoir, a cold water reservoir, means establishing a feed connection from the cold water to t e hot water reservoir, means establishing connection from the hot water to i the cold water reservoir, a thermostatically actuated diversion valve interposed in the pipe leading from said hot water reservoir to said source of heat and adapted to divert the flow into said cold water reservoir when the hot water attains a predetermined temrature, and means actuated by-variations 1n water levelin said hot water reservoir controlling the first'named connection".

8; In apparatus of the'kind'specified, a

hot water reservoir, a cold water reservoir, means establishing feed connection from the latter to the former, means actuated .by variations in water level in said hot water reservoir. controlling said connection, means establishing connection from the hot water to the cold water reservoir, a valve-con-v trolling water in said hot water reservoir controlling said valve' 9. In apparatus of the kindspe'cified, a hot water reservoir, a cold water reservoir, means establishing connection from each thereof to the other for effecting an inter change of water, a thermostatically actuated valve controlling the flow of hot; water to said cold water reservoir, and means actuated by decrease of'wate'r level in said hotwater reservoir due to the flow therefrom into saidcold water reservoir for-establishing feed connection from said cold water to said hot water reservoir to reestablish the normal water level therein, \vhcrebyTeduction of the temperature of the hot water is efi'ected.

10. Iii-apparatus of the kind specified, a hot water reservoir, a cold water reservoir, a constantly active heater delivering into said hot water reservoir, a normally 'inactive heater in the latter. connection respectively from each of said reservoirs to said constantly active heater, a single pump.

interposed in said connections, a bv-pass connection from the delivery end of said pump to said cold water reservoir, a -valve controlling said conneetioma valve controlling said normally inactiv'e heater, a thermostatically actuated lever having operative connection with each of said valves, said lever controlled by variations in temperature of the hot water and adapted when said temperature falls to (men. said last'namedvalve and when said temperature rises to.

close both said valves at respectively different intervals, the valve controlling said bypass connection when closcd causing flow from said hot water to said cold water ressaid connection, and a lever actuated by variations in temperature of the ervoir whereby the water level in the former is reduced. a float in said hot water reservoir, a valve controlled thereby and controlling the flow from the cold water to the hot water reservoir and adapted to be opened by said decrease in water level, and a bypass connection Between the delivery end of said pump and said heater for feeding the latter during the interval of flow of hot water to said cold water reservoir, substantially as and for the purposespecified.

11. In apparatus of the kindspecified, a hot water reservoir, a constantly active heater delivering thereto, a return connection from reservoir to said heater, a pump interposed in said connection serving to maintain the vatcr of sait l reservoir in constant circulation through said' heater, a valve interposed in said connection, a cold water supply connected \vi'tlitlic suction end of saidpump, a valve interposed in said connection, a float in said reservoir actuating both said valves, the last-named valve being normally closed and the first-named normally open and adapted to be closed as the other opens, means for maintaining parallel parts of said respective connections rigid with each other at. one vpoint, alever p1v'ot ally, secured to each of'said parallel parts and adapted to be swung bycxpansmn and contraction ofthe hot water connection-i relatively to the cold water connection due,

to variations in tei nperature in the water of said reservoir, a valve interposed inthe delivery pipe from said pump, a. by-pass' hot water discharge connection from said delivery pipe controlled-by said valve, and

connection between "said valve. and saidlever to close said valve ,when the water in the reservoir attains apredetermined mam- -mum temperature, whereby hot water is discharged and the water level in the reservoir reduced, thereby opening the cold water connection to said pump, there being an opening in said valve for the passage of part of the water delivered by said pump through said heater into said reservoir, substant-ially as and for the purpose specified.

water reservoir, a constantly active heater delivering thereto, a return connection from said reservoir to said heater, a pump inter-,1 posed in said connection serving to maintain" respective connections rigid wit i each other at one point, a lever pivotally secured to each of said parallel parts and adapted tobe swung by expansion and contraction of the hotwater connection relatively'to the cold water connection due to variations in tem- 12. In apparatus of the kind specified, a hot perature in the water of said reservoir, a

saidpump, a-by-pass hot waterdischarge connection from said 5 ivery pipe controlled by said valve, and connection between said valve and said lever to close said valve when the water inthe reservoir attains a predetermined maximum temperature, and means for adjusting the time of closure of said' valve relatively to the arc of movement of said lever whereby the maxinuun temperature attainable by the hot water may be varied, said valve, when closed,

said by-pass and reducing the water level in the reservoir, thereby openingthe cold water connection to said pump, there being part of the water delivered by said pump through said heater into said reservoir, substantially as and for the purpose specified.

13; In. apparatus: of the kind specified, means-for fixing the" maximum temperature attainable by the water comprising a constantlyactive heater delivering into the hot water reservoir, 9; pump delivering into said heater, connection between the suction end of said pump and said reservoir, a normally open valve in said connection, connection between the suction end of said pump and a 1d water supply, a normally closed valve in said connection, a float in said reservoir adapted tosimultaneously actuate .said valves in respectively reverse direction when the water level in said reservoir falls, :1 normally inactive discharge connection from the delivery end of said pump for-Withdrawing water, a valve controlling the same, and means-actuated by variations in temperature in the water of said reservoir controlling said valve, the latter when actuated in one direction causing a partial discharge through said discharge connection whereby the water level in said reservoir is reduced and the cold water supply connection opened, part of the water delivered by said amp passing into the reservoir through the saidheater until the temperature of the reservoir water has "named valve 18' returned to its normal position. v j

14. In apparatus of the kind specified, a; constantly; active heater, :1, hot \vater reser therefrom tiroughsaid heater to increase the temperature thereof, a cold water reserend of said amp, and a thermostatically controlled va 've inter osed in said connection and 'ada ted to e ect an interchange of thewaters 0 said reservoirs to prevent the attainment of more than a predetermined maximum temperature of'the water in said hot water reservoir.

valve'interposed in the delivery pipe from causing adischarge of hot water throng-1r an opening in said valve for the passage of receded to a given point, whereby the last- 'voir, a pain for continuously passing water I 'voir, normally closed 1 connection between said cold water"reservoir and the delivery' in said connection for varying the periods of operation of said valve 15. In apparatus of the kind specified, a heater 7 constantly active heater, a hot Water reser voir, means for continuously passing water therefroi'n through said heater to increase the temperature thereof, a cold water reservoir, means for elt'ecting an interchange of the Waters of said reservoirs, a Valve controlling said means, a thern'iostatieally actuated member queratively connected. with and controlling said valve, and means interposed relatively to the movement 01' said member, whereby the ten1- perature attainable by the hot water before effecting said interchange of waters is controlled.

16. In apparatus of the kind specified, a hot-water reservoir, a normally inactive l l l l name in presence of two subscribing witnesses.

JOHN E. CAPS. Vitnesses M. M. BoYLn, H. L. HALE. 

